// Copyright (c) 1994-2006 Sun Microsystems Inc.
// All Rights Reserved.
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// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// The original source code covered by the above license above has been
// modified significantly by Google Inc.
// Copyright 2012 the V8 project authors. All rights reserved.

// A light-weight IA32 Assembler.

#ifndef V8_IA32_ASSEMBLER_IA32_INL_H_
#define V8_IA32_ASSEMBLER_IA32_INL_H_

#include "src/ia32/assembler-ia32.h"

#include "src/assembler.h"
#include "src/debug/debug.h"
#include "src/objects-inl.h"

namespace v8 {
namespace internal {

    bool CpuFeatures::SupportsOptimizer() { return true; }

    bool CpuFeatures::SupportsWasmSimd128() { return IsSupported(SSE4_1); }

    // The modes possibly affected by apply must be in kApplyMask.
    void RelocInfo::apply(intptr_t delta)
    {
        DCHECK_EQ(kApplyMask, (RelocInfo::ModeMask(RelocInfo::CODE_TARGET) | RelocInfo::ModeMask(RelocInfo::INTERNAL_REFERENCE) | RelocInfo::ModeMask(RelocInfo::OFF_HEAP_TARGET) | RelocInfo::ModeMask(RelocInfo::RUNTIME_ENTRY)));
        if (IsRuntimeEntry(rmode_) || IsCodeTarget(rmode_) || IsOffHeapTarget(rmode_)) {
            int32_t* p = reinterpret_cast<int32_t*>(pc_);
            *p -= delta; // Relocate entry.
        } else if (IsInternalReference(rmode_)) {
            // absolute code pointer inside code object moves with the code object.
            int32_t* p = reinterpret_cast<int32_t*>(pc_);
            *p += delta; // Relocate entry.
        }
    }

    Address RelocInfo::target_address()
    {
        DCHECK(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_) || IsWasmCall(rmode_));
        return Assembler::target_address_at(pc_, constant_pool_);
    }

    Address RelocInfo::target_address_address()
    {
        DCHECK(HasTargetAddressAddress());
        return pc_;
    }

    Address RelocInfo::constant_pool_entry_address()
    {
        UNREACHABLE();
    }

    int RelocInfo::target_address_size()
    {
        return Assembler::kSpecialTargetSize;
    }

    HeapObject RelocInfo::target_object()
    {
        DCHECK(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);
        return HeapObject::cast(Object(ReadUnalignedValue<Address>(pc_)));
    }

    Handle<HeapObject> RelocInfo::target_object_handle(Assembler* origin)
    {
        DCHECK(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);
        return Handle<HeapObject>::cast(ReadUnalignedValue<Handle<Object>>(pc_));
    }

    void RelocInfo::set_target_object(Heap* heap, HeapObject target,
        WriteBarrierMode write_barrier_mode,
        ICacheFlushMode icache_flush_mode)
    {
        DCHECK(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);
        WriteUnalignedValue(pc_, target->ptr());
        if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
            FlushInstructionCache(pc_, sizeof(Address));
        }
        if (write_barrier_mode == UPDATE_WRITE_BARRIER && !host().is_null()) {
            WriteBarrierForCode(host(), this, target);
        }
    }

    Address RelocInfo::target_external_reference()
    {
        DCHECK(rmode_ == RelocInfo::EXTERNAL_REFERENCE);
        return ReadUnalignedValue<Address>(pc_);
    }

    void RelocInfo::set_target_external_reference(
        Address target, ICacheFlushMode icache_flush_mode)
    {
        DCHECK(rmode_ == RelocInfo::EXTERNAL_REFERENCE);
        WriteUnalignedValue(pc_, target);
        if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
            FlushInstructionCache(pc_, sizeof(Address));
        }
    }

    Address RelocInfo::target_internal_reference()
    {
        DCHECK(rmode_ == INTERNAL_REFERENCE);
        return ReadUnalignedValue<Address>(pc_);
    }

    Address RelocInfo::target_internal_reference_address()
    {
        DCHECK(rmode_ == INTERNAL_REFERENCE);
        return pc_;
    }

    Address RelocInfo::target_runtime_entry(Assembler* origin)
    {
        DCHECK(IsRuntimeEntry(rmode_));
        return ReadUnalignedValue<Address>(pc_);
    }

    void RelocInfo::set_target_runtime_entry(Address target,
        WriteBarrierMode write_barrier_mode,
        ICacheFlushMode icache_flush_mode)
    {
        DCHECK(IsRuntimeEntry(rmode_));
        if (target_address() != target) {
            set_target_address(target, write_barrier_mode, icache_flush_mode);
        }
    }

    Address RelocInfo::target_off_heap_target()
    {
        DCHECK(IsOffHeapTarget(rmode_));
        return Assembler::target_address_at(pc_, constant_pool_);
    }

    void RelocInfo::WipeOut()
    {
        if (IsEmbeddedObject(rmode_) || IsExternalReference(rmode_) || IsInternalReference(rmode_)) {
            WriteUnalignedValue(pc_, kNullAddress);
        } else if (IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_) || IsOffHeapTarget(rmode_)) {
            // Effectively write zero into the relocation.
            Assembler::set_target_address_at(pc_, constant_pool_,
                pc_ + sizeof(int32_t));
        } else {
            UNREACHABLE();
        }
    }

    void Assembler::emit(uint32_t x)
    {
        WriteUnalignedValue(reinterpret_cast<Address>(pc_), x);
        pc_ += sizeof(uint32_t);
    }

    void Assembler::emit_q(uint64_t x)
    {
        WriteUnalignedValue(reinterpret_cast<Address>(pc_), x);
        pc_ += sizeof(uint64_t);
    }

    void Assembler::emit(Handle<HeapObject> handle)
    {
        emit(handle.address(), RelocInfo::EMBEDDED_OBJECT);
    }

    void Assembler::emit(uint32_t x, RelocInfo::Mode rmode)
    {
        if (!RelocInfo::IsNone(rmode)) {
            RecordRelocInfo(rmode);
        }
        emit(x);
    }

    void Assembler::emit(Handle<Code> code, RelocInfo::Mode rmode)
    {
        emit(code.address(), rmode);
    }

    void Assembler::emit(const Immediate& x)
    {
        if (x.rmode_ == RelocInfo::INTERNAL_REFERENCE) {
            Label* label = reinterpret_cast<Label*>(x.immediate());
            emit_code_relative_offset(label);
            return;
        }
        if (!RelocInfo::IsNone(x.rmode_))
            RecordRelocInfo(x.rmode_);
        if (x.is_heap_object_request()) {
            RequestHeapObject(x.heap_object_request());
            emit(0);
        } else {
            emit(x.immediate());
        }
    }

    void Assembler::emit_code_relative_offset(Label* label)
    {
        if (label->is_bound()) {
            int32_t pos;
            pos = label->pos() + Code::kHeaderSize - kHeapObjectTag;
            emit(pos);
        } else {
            emit_disp(label, Displacement::CODE_RELATIVE);
        }
    }

    void Assembler::emit_b(Immediate x)
    {
        DCHECK(x.is_int8() || x.is_uint8());
        uint8_t value = static_cast<uint8_t>(x.immediate());
        *pc_++ = value;
    }

    void Assembler::emit_w(const Immediate& x)
    {
        DCHECK(RelocInfo::IsNone(x.rmode_));
        uint16_t value = static_cast<uint16_t>(x.immediate());
        WriteUnalignedValue(reinterpret_cast<Address>(pc_), value);
        pc_ += sizeof(uint16_t);
    }

    Address Assembler::target_address_at(Address pc, Address constant_pool)
    {
        return pc + sizeof(int32_t) + ReadUnalignedValue<int32_t>(pc);
    }

    void Assembler::set_target_address_at(Address pc, Address constant_pool,
        Address target,
        ICacheFlushMode icache_flush_mode)
    {
        WriteUnalignedValue(pc, target - (pc + sizeof(int32_t)));
        if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
            FlushInstructionCache(pc, sizeof(int32_t));
        }
    }

    Address Assembler::target_address_from_return_address(Address pc)
    {
        return pc - kCallTargetAddressOffset;
    }

    void Assembler::deserialization_set_special_target_at(
        Address instruction_payload, Code code, Address target)
    {
        set_target_address_at(instruction_payload,
            !code.is_null() ? code->constant_pool() : kNullAddress,
            target);
    }

    int Assembler::deserialization_special_target_size(
        Address instruction_payload)
    {
        return kSpecialTargetSize;
    }

    Displacement Assembler::disp_at(Label* L)
    {
        return Displacement(long_at(L->pos()));
    }

    void Assembler::disp_at_put(Label* L, Displacement disp)
    {
        long_at_put(L->pos(), disp.data());
    }

    void Assembler::emit_disp(Label* L, Displacement::Type type)
    {
        Displacement disp(L, type);
        L->link_to(pc_offset());
        emit(static_cast<int>(disp.data()));
    }

    void Assembler::emit_near_disp(Label* L)
    {
        byte disp = 0x00;
        if (L->is_near_linked()) {
            int offset = L->near_link_pos() - pc_offset();
            DCHECK(is_int8(offset));
            disp = static_cast<byte>(offset & 0xFF);
        }
        L->link_to(pc_offset(), Label::kNear);
        *pc_++ = disp;
    }

    void Assembler::deserialization_set_target_internal_reference_at(
        Address pc, Address target, RelocInfo::Mode mode)
    {
        WriteUnalignedValue(pc, target);
    }

    void Operand::set_sib(ScaleFactor scale, Register index, Register base)
    {
        DCHECK_EQ(len_, 1);
        DCHECK_EQ(scale & -4, 0);
        // Use SIB with no index register only for base esp.
        DCHECK(index != esp || base == esp);
        buf_[1] = scale << 6 | index.code() << 3 | base.code();
        len_ = 2;
    }

    void Operand::set_disp8(int8_t disp)
    {
        DCHECK(len_ == 1 || len_ == 2);
        *reinterpret_cast<int8_t*>(&buf_[len_++]) = disp;
    }

} // namespace internal
} // namespace v8

#endif // V8_IA32_ASSEMBLER_IA32_INL_H_
